TUESDAY, Jan. 7, 2014 (HealthDay News) -- The rate of cancer deaths among Americans continues to decline, according to a new report. Over the last 20 years, the overall risk of dying from cancer has dropped 20 percent, researchers found.

The fastest decline in cancer death risk has been among middle-aged black men, for whom death rates have dropped by about 50 percent, the study authors report.

"We continue to make progress against cancer," said report co-author Ahmedin Jemal, vice president for surveillance and health services research at the American Cancer Society.

But despite this progress, black men still have the highest cancer incidence and death rates of all groups -- about double those for Asian Americans, who have the lowest rates, the authors pointed out in a news release from the American Cancer Society.

The decline in cancer deaths from 1991 to 2010 varied by age, race and sex, researchers found. For example, there was no decline in deaths for white women 80 and older, but a 55 percent decline among black men aged 40 to 49 years old.

This progress is largely because of better prevention, screening and treatment, Jemal said. The dramatic decline in cancer among black men is most likely attributable to decreases in smoking, he added.

Jemal said most of the progress has been made in colon, breast and prostate cancer. These cancers can be screened for and, when caught early, have better outcomes, he said.

In addition, decreased smoking has reduced the number of lung cancers, Jemal said.

But some cancers, such as pancreatic cancer, for which there is no screening and for which treatment often comes too late, remain just as deadly, he said.

Jemal, however, expects a brighter future as screening increases as more Americans get access to health insurance through the Affordable Care Act. Not having insurance is the biggest barrier to screening, he explained.

Still, more needs to be done to close the improvement gap between races, an expert said.

"The halving of the risk of cancer death among middle-aged black men in just two decades is extraordinary, but it is immediately tempered by the knowledge that death rates are still higher among black men than white men for nearly every major cancer and for all cancers combined," John Seffrin, chief executive officer of the American Cancer Society, said in a society news release.

The report was published Jan. 7 in CA: A Cancer Journal for Clinicians.

Dr. Anthony D'Amico, chief of radiation oncology at Brigham and Women's Hospital in Boston, said, "The good news is that the rate of deaths has declined again for almost the 10th consecutive year."

D'Amico also believes that these declines are the result of better screening, especially screening for prostate cancer. In addition, new treatments are reducing deaths, he said.

"Something good is happening and I would attribute that to screening and better treatments," D'Amico said. "We have better treatments for men and women, so screening can only help," he added.

In 2014, it's estimated there will be over 1.6 million new cancer cases and nearly 586,000 cancer deaths in the United States, according to the report. Although the number of new cancers and cancer deaths continues to increase as the population increases and ages, the rate of new cancers and cancer deaths is declining, Jemal explained.

For men, prostate, lung and colon cancer will make up half of all newly diagnosed cancers. Prostate cancer alone will account for about one-quarter of the cases, the researchers estimate.

Among women, the most common cancers will be breast, lung and colon cancer. Taken together, these will account for half of all cases. Breast cancer alone is estimated to account for 29 percent of all new cancers.

In 2014, about 1,600 people will die from cancer each day, the report estimates. Lung, colon, prostate and breast cancers are the most common causes of cancer death. These account for almost half of the all cancer deaths. Just over one in four cancer deaths is from lung cancer, the researchers noted.

From 2006 to 2010, cancer rates dropped 0.6 percent per year among men while remaining stable among women. During the same time, death rates from cancer dropped by 1.8 percent per year among men and 1.4 percent per year among women, the investigators found.

Moreover, during the last 20 years, the death rate from cancer has continued to drop from a high of about 215 per 100,000 people to about 172 per 100,000 people in 2010. This means that 1,340,400 fewer cancer deaths (952,700 among men and 387,700 among women) were avoided during that time period, the researchers explained.